America's power plants deliver electrical power for residential, commercial, and industrial use almost exclusively via high voltage alternating current (AC). However, an increasing percentage of devices found in such residences, businesses, and factories operate on low voltage direct current (DC) electrical power. For example, nearly all products that utilize rechargeable batteries, e.g., laptops, cellular telephones, smart phones, etc., require low voltage DC for power management and/or recharging of the device. Thus, the devices that utilize low voltage DC typically require transformer “bricks” that convert the AC voltage exiting typical electrical outlets to the DC voltage necessary to power such devices.
But these transformer “bricks” are not an efficient use of space and oftentimes do not efficiently convert AC voltage to DC voltage; that is, the conversion process usually wastes electricity. The cost of wasted electricity may be small for any particular device but can grow very large across an entire residence, office workspace, factory, etc. But today, with current DC loads including LED lighting and monitors, it is conceivable with efficient energy conversion, that a modern office can uses as little as 100 W of power. Also, Uninterruptible Power Supplies (UPS) for offices provide backup to the AC loads plugged into them by inverting the DC power stored in their internal batteries. With batteries as DC storage units, and the loads predominantly DC, a DC-based power delivery buss system with battery is simpler and more efficient and consequently the same capacity battery can provide backup power for a longer period by avoiding “double conversion.” Additionally, as the trend toward energy efficiency grows, it is possible that buildings could directly receive DC voltage instead of AC voltage from alternative sources such as solar panels, wind turbines, etc. In such cases, these DC power sources would need to be converted to AC to work with the transforming bricks that will then convert back to low voltage DC. This is another form of “double conversion” that is even less efficient than the current situation. In any case, there is an identifiable need to bring low voltage DC power into the office workspace in a manner that promotes efficient energy usage and efficient workspace usage.
Further, as mentioned above, there is a trend towards efficient energy use in commercial buildings. For example, there is a push to reduce energy consumption from both plug loads and lighting, which can comprise approximately 20-30% and 20-25%, respectively, of total energy consumption in an office, retail, or other commercial space. The trend to reduce energy consumption in these buildings is driven by, among other things, energy use regulations. For example, certain energy use regulations require plug loads and lighting to be de-energized when the workspace is unoccupied.
To comply with such regulations in an office, it is known in the art that advanced power strips (APS) that plug into traditional 120 volt alternating current outlets can cut power to the desk top fixtures based on a control method (e.g., time or occupancy sensing). However, APS have limited functionality. Most APS can accommodate only a fixed, small number of plug loads and many times the transformer “bricks” cannot fit into adjacent sockets leading to more office workspace clutter. Moreover, APS are often bypassed by the office occupant due to inconvenient location or nuisance shutdowns, thus eliminating any energy savings.
As an alternative to APS, there is also an increased use of Building Management Systems (BMS) to save electricity in the commercial building environment. BMS may control numerous aspects of a building's energy use infrastructure, including, for example, overhead lighting. BMS, however, are complicated and expensive to implement in both new construction and existing buildings. Thus, there is an identifiable need for a lower cost, robust energy use reduction system to shed plug loads at a more local level in locations such as the office workspace environment.
Still further, as the work force becomes more mobile and flexible, the office workspace is also moving from an individual employee-centric workspace to a shared office workspace environment. For example, an office workspace may be occupied by an outside sales person in the morning, and then by a field technician in the afternoon, requiring quick and easy adjustments to accommodate the different needs of each occupant. Such different needs depend upon, for example, each occupant's dominant hand, height, personal preferences, physical limitations, and job duties. Accordingly, mechanically adjustable office furniture is a growing trend.
The increased need for mechanically adjustable office furniture is also driven by the trend towards smaller offices. Typical office workspaces have shrunk as businesses are attempting to use smaller and smaller office workspaces to curb costs and/or to encourage collaboration among colleagues. These smaller office workspaces have correspondingly smaller work surfaces. Mechanically adjustable shelving systems help lift various devices, e.g., phones, monitors, computers, etc., off the work surface to free-up additional work surface area for occupant use. One drawback of the currently available mechanically adjustable shelving systems is that they fail to address the electrical requirements of devices and force their power cords to dangle, which is both an eyesore and contributes to clutter of the already smaller office workspace. Because low voltage DC poses no real electrical shock risk, its use in office workspace enables readily accessible power for these devices. Thus, there is an identifiable need for improved mechanically adjustable office furniture that can be attained by bringing low voltage DC power into the office workspace efficiently.
To help achieve an energy efficient workspace, as previously mentioned, lighting is a target for reduction due to its contribution to the electrical bill of an office. Advances such as occupancy sensing and LED technology are helping reduce this energy use, but these lighting fixtures have limitations due to where the power enters the fixture and where the light output is needed. Additionally, LED technology brings new challenges to lighting in that the LED chips themselves need to be kept cool to achieve long life. Free standing light fixtures today usually have a base that rests on a surface, and electrical power comes through that base, travels up a neck to the socket and lamp so that the electrical power can be turned into light to be cast back down on the work surface. In all fixtures, this requires the electrical system to be routed through the entire fixture. In LED lighting, it requires a heat sink (normally made of a large mass of metal) at the top of the fixture. This can make the fixture top heavy, but also doesn't take advantage of the mass normally at the base of fixtures to prevent tipping. LED Luminaires that use edge lighting of clear panels can address some of these requirements, but they cast the light predominantly 90 degrees from the direction the light is emitted from the LED source, which doesn't direct the majority of the light toward the work surface where it is needed but into the face of the person at the work space. Consequently, there is also a clear need for light fixtures that have a light source near the base, but can also direct most of the light output back in the direction of the surface on which the base rests.